Anti-bubble safety valve for a liquid-circuit

Abstract

The anti-bubble safety valve comprises a liquid-admission chamber which is partly delimited by a diaphragm in cooperating relation with a seating provided with an outlet pipe. Thus the liquid which is present within the chamber is directed into the diaphragm-seating interface and passed in laminar flow towards the outlet pipe. The chamber is provided with a passageway to the surrounding atmosphere for the discharge of any air bubble which may have been admitted.

I claim: 
     
       1. An anti-bubble safety device for a low pressure liquid circuit and especially for medical perfusion, comprising a bag including a flexible wall and forming a chamber for the admission of liquid; a valve comprising a diaphragm forming a part of said flexible wall; a seating for said diaphragm formed by a plate having a peripheral edge to which is bonded said diaphragm, said diaphragm and seating forming an interface and comprising at least one liquid circulation passageway through the plate from the interior of the bag to the interface; and an outlet duct extending through said plate which is in laterally spaced relation with said at least one liquid circulation passageway so as to impose a laminar flow of the liquid in the interface between said passageway and said outlet duct, said outlet duct being adapted to be connected to an outlet pipe extending outwardly of the bag and said bag being provided with a passageway to the surrounding atmosphere. 
     
     
       2. A safety device as claimed in claim 1, wherein the bag includes suspension means for suspending the device, and wherein the device further comprises three pipes associated with the base of the bag, one pipe being provided for admission of the liquid into the bag, a second pipe being connected to the outlet duct, and a third pipe extending to the top portion of said bag and forming part of said passageway to the surrounding atmosphere. 
     
     
       3. A safety device as claimed in claim 3, wherein the bag is a flexible bag and has a pocket formed by bonding the bag walls to a level below that of the top of the third pipe so that said bag constitutes a liquid overflow volume in the event of overpressure which prevents normal discharge of the liquid through the device.